In this lesson plan students conduct a survey of ten students, collect data in a tally chart, and then display and analyze the results in a bar graph. In the analysis students must compare numbers, add, and subtract using the data in the bar graph to generate questions as well as answer them. The lesson plan includes a graph template, a link to an interactive graphing tool, extension questions, and a fact family sheet to show the related facts from their graph analysis.

The stated mission of this blog is "To make the nightly math problem as common as the bedtime story." Each day Laura Bilodeau Overdeck and her husband John post an interesting fact or scenario about everyday life and related math problems at three readiness levels. They include a page of suggestions for how to use these problems with children. This is a good source of problems for teachers and parents, as well as a model for adapting problems to meet different needs.

This iOS app for the online site Bedtime Math (cataloged separately) offers a problem of day as well as a database of over 400 problems that cover a range of topics that the user may explore. Each problem of the day includes background information and four levels of problem solving options (Wee Ones, Little Kids, Big Kids, and the Sky's the Limit). Each problem includes an answer.

In this 8-lesson unit students use buttons to explore logical and numerical relationships that form the conceptual basis for understanding addition and subtraction operations. Topics include counting, ordinal numbers (and relative position), classification (attributes), relationships between numbers, addition of sets, commutativity of addition, sums to 10, fact families (including subtraction), three models of subtraction ("take away", comparative, missing addend), and bar graphs. Includes student activity sheets and a link to an online graphing applet.

In this 8-minute video kindergarten teacher Karen Lassiter models a lesson designed to help children understand place value with the numbers 11-19. She explains her use of a 10-frame in developing understanding of counting on, addition, and notation. The resource includes reflection questions for viewers, a transcript of the video (doc), and a lesson plan (pdf).

This problems is an opportunity to explore triangular numbers in the familiar context of decorating a birthday cake with a number of candles corresponding to a child's age. The problem lends itself to systematic strategies and multiple representations. The Teachers' Notes page offers rationale, suggestions for implementation, discussion questions, and ideas for extension and support.

This problem provides an opportunity for students to develop problem solving skills while applying skip-counting and exploring the concepts of multiples and factors within 20. It is posed in the context of toppings on cookies ("biscuits" in the UK) and lends itself to multiple representations. The Teachers' Notes page offers suggestions for implementation, discussion questions, ideas for extension and support, and downloadable handouts.

In this problem students explore the concept of proportion by comparing the relative strengths of different mixes of juice flavor and water in a visual context. Given four mixtures represented by purple and white rectangles, students order the drinks from strongest to weakest flavor and explain their reasoning. The Teachers' Notes page offers suggestions for implementation, discussion questions, and ideas for extension and support.

In this Illuminations lesson plan students explore the use of variables as they solve for the weights of objects using information presented in pictures. Learners model situations that involve adding and subtracting whole numbers, using objects, pictures, and symbols. A student activity sheet is available and downloadable (pdf).

This interactive applet introduces students to the topic of combinations, a basic concept in probability. Users create combinations of shirts and pants to determine the total number of possible outfits. They may simply explore by placing the clothes on Bobbie, or make a guess and then test it. The number of shirt and pants choices is customizable. An optional voice provides prompts and feedback.